The graph about China is not convincing at all. You are looking at variation over time, so time trends where the US sector is trending down while the Chinese is trending up would easily generate such a strong correlation. I am actually a bit surprised it is not stronger (it must have to do with business cycles).

By Maggie McMillan, guest blogger When economists talk about structural transformation, they typically have in mind developing countries and the dual economy models à la W. Arthur Lewis that emphasize productivity differentials between broad sectors of the economy, such as agriculture and manuf...

Some of the pattern might be mechanically driven by demographic transition. High population growth at first that washes out productivity gains and the transition kicks in at some point.
Very interesting, in any case!

During the course of research my co-author Maggie McMillan and I were doing on broad patterns of structural change, our research assistant Inigo Verduzco stumbled on an interesting stylized fact that is captured in the figure below. What it shows is that the relative productivity of agricultur...